Minnesota Vikings tight end John Carlson's season took an unfortunate, and predictable, turn on Saturday when the team placed him on injured reserve following his fifth documetned concussion in a Dec. 8 loss at Baltimore. He missed Sunday's win over the Eagles and will miss the Vikings' final two games at the Cincinnati Bengals and season finale against the Detroit Lions.

Carlson, 29, has a history of brain injuries that dates back to two reported concussions while at Notre Dame. In January 2011, Carlson hit his head on the frozen turf at Soldier Field in the Seattle Seahawks' playoff loss at the Chicago Bears for his third concussion. In 2012, Carlson missed two games in his first season with the Vikings due to his fourth concussion.

Coach Leslie Frazier said the team would mull over placing Carlson on injured reserve this week and ultimately pulled the trigger on Saturday. As far as what this means for Carlson's career, Frazier said Friday that the two had yet to talk about it, but eventually would.

In March, Carlson accepted a restructure that cut his base salary from $2.9 million to $1.5 million in 2013 -- a year after they signed him to a five-year, $25 million deal even though he'd sat out the previous season in Seattle. Limited by injuries and dwarfed by Kyle Rudolph's nine-touchdown, Pro-Bowl season last year, Carlson finished 2012 with career lows in receptions (eight), yards (43) and touchdowns (none).

The Fighting Irish product had a career game in his first start in place of Kyle Rudolph this season, when he caught all seven passes thrown his way for 98 yards and a touchdown in a Nov. 7 win over the Washington Redskins.

Vikings waive Steeples, elevate two

With the Carlson move, the Vikings also waived cornerback Robert Steeples and elevated two practice squad players.

Defensive end Justin Trattou and running back Joe Banyard were promoted to the active roster. Banyard saw limited snaps behind Asiata last week and was downgraded back to the practice squad. His promotion could indicate that Asiata or Peterson, both listed as questionable, can't go on Sunday at Cincinnati.

Peterson and coach Leslie Frazier were both confident that the NFL MVP would return to the field this week after sitting out last week with a mid-foot sprain he suffered in the Dec. 8 loss at Baltimore.